She spoke to Campaign after the publication this week of a report from the Department for Culture, Media and Sport’s Women’s Business Council, on which she sits.
The report found that GDP could be boosted by 10 per cent if women and men were equally represented in the UK workforce by 2030.
Some agencies fail to motivate female staff, Snowball said: "I’m lucky to work in a company where gender is no obstacle. I know it’s not the same everywhere. We have to fix that."
The report called on government and business to take actions such as improving careers advice for girls and equipping women with the skills to launch their own businesses.
The research stressed the need for more opportunities for women in the "third phase" of their careers in their fifties and sixties.
Snowball said this has particular relevance to the ad industry: "We’re a very young business where the average age is 34. The report suggests there is scope to develop talent much more broadly at all ages and stages."
She added: "The numbers in the 2012 IPA Census shows we’re diverse as an industry and women account for 49 per cent of the workforce. But there is lots more we can do to support and develop the pipeline at an industry level."